First report of a blaNDM-5-carrying Escherichia coli sequence type 12 isolated from a dog with pyometra in Japan.

Carbapenemase-producing Enterobacterales (CPE) are a serious concern in human clinical settings. Companion animal-origin CPE have been only rarely identified in several countries, but they have not yet been identified in Japan. In this study, we present the first case of a canine infected with CPE in Japan. The patient was hospitalized due to pyometra. The pus discharged from the patient's uterus was subjected to bacteriological analysis. As a result, E. coli was identified in the pus and exhibited resistance to piperacillin, amoxicillin-clavulanic acid, cefazolin, ceftazidime, cefepime, meropenem, amikacin, and sulfamethoxazole-trimethoprim and susceptibility to aztreonam, minocycline, and levofloxacin. Results of the sodium mercaptoacetic acid double-disk synergy test showed that the E. coli isolate was positive for metallo-ß-lactamases. Next-generation sequencing identified the blaNDM-5 gene, which was located in the IncFII-type plasmid together with blaTEM-1b, rmtB, aadA2, bleMBL, sul1, qacE, and dfrA12. The case was treated successfully with doxycycline and orbifloxacin. Our finding emphasizes that close attention should be paid to the significance of CPE harboring multidrug-resistance plasmid in companion animals, based on the perspective of One Health approach in Japan as well as in other countries.

Antimicrobial resistance in Enterobacteriaceae isolated from arthropods in Gifu City, Japan.

The wide occurrence of antimicrobial-resistant (AMR) bacteria in various environments is of great concern. Here, we examined the prevalence and antimicrobial susceptibility of Enterobacteriaceae isolated from 88 wild arthropods, collected in Gifu city, Japan. In total, 168 isolates of Enterobacteriaceae were obtained from 61 arthropods. All isolates were susceptible to all the antimicrobial agents tested, except colistin (31 isolates) and kanamycin (one isolate). The aph(3')-Ia gene, responsible for kanamycin resistance, was detected in Klebsiella oxytoca. Although synanthropic arthropods (houseflies and cockroaches) serve as vectors for AMR Enterobacteriaceae, other wild arthropods are not crucial carriers of Enterobacteriaceae resistant to antimicrobial agents.

Persistence of extended-spectrum ß-lactamase plasmids among Enterobacteriaceae in commercial broiler farms.

To clarify the persistence of extended-spectrum ß-lactamase (ESBL) producers, 13 plasmids from two broiler farms were analyzed. On the farm not using antimicrobials, one plasmid from Klebsiella pneumoniae isolated from a day-old chick was similar to that from Escherichia coli isolated a year later, with the deletion of two transposons. On the farm using antimicrobials, most circulating plasmids (eight out of nine) in a flock of 40-days-old chicks were identical, although one from K. pneumoniae had a deletion of a transposon carrying a class 1 integron containing aadA2 and dfrA12. Thus, ESBL plasmids persisted in the farms with or without antimicrobial agent use.

Efficacy of raloxifene hydrochloride for the prevention of health care problems in patients who undergo surgery for endometrial cancer: a multicenter randomized clinical trial.

OBJECTIVE: Removal of the ovaries is common during surgery for endometrial cancer. However, because loss of the ovaries can cause several health problems in patients, strategies for the prevention of such problems need to be established. Hence, we decided to conduct a multicenter randomized clinical trial to assess the effect of raloxifene on bone mineral density (BMD), bone metabolism, and the lipid profile of patients who had undergone surgery for patients with endometrial cancer. MATERIALS AND METHODS: Patients with endometrial cancer were enrolled after treatment. The participants were randomized into 2 groups: group 1 included 39 women who received alfacalcidol (1 µg/d) alone and group 2 included 37 women who received alfacalcidol and the test drug, raloxifene hydrochloride, at a dose of 60 mg/d. The BMD of lumbar spine and femoral neck, serum bone markers, as well as lipid profile parameters were evaluated at enrollment as well as 6, 12, and 24 months after the enrollment. The primary efficacy end point was the percentage change from baseline to 24 months in lumbar spine (L2-L4) and femoral neck BMD. RESULTS: Sixty-four women completed the 24-month study. At 24 months, the lumbar and femoral neck BMDs were significantly increased in group 2 compared with group 1 (3.5% vs -0.8% and 2.3% vs -2.8%, respectively). In group 2, low-density lipoprotein-cholesterol levels were significantly reduced by 13.6% and serum N-terminal telopeptide of type I collagen as well as bone-specific alkaline phosphatase values were significantly reduced by 16.7% and 25.7%, respectively. The patients who received adjuvant therapy for endometrial cancer showed a significantly higher response to raloxifene (5.8% vs 1.9%). Recurrence was detected in 2 (2.6%) patients in group 1. No severe adverse events were noted in any patient during the study period. CONCLUSIONS: Raloxifene exerts positive effects on BMD, bone metabolism, and lipid profile parameters and could provide an improved therapeutic option for patients with endometrial cancer.

Characterization of quinolone-resistant and extended-spectrum ß-lactamase-producing Escherichia coli derived from sika deer populations of the Nara Prefecture, Japan.

Wildlife in urban areas have the potential to disseminate antimicrobial-resistant bacteria (ARB) across a wider environment. Using antimicrobial-supplemented agar plates, we isolated extended-spectrum ß-lactamase-producing Escherichia coli (EEC) and quinolone-resistant E. coli (QREC) from 144, 23, and 30 deer feces from Nara Park (NP), rural area neighboring NP (RA), and Mt. Odaigahara (MO), respectively. In NP and RA, the prevalence of EEC was 24.3 and 4.3%, respectively; that of QREC was 11.1 and 17.4%, respectively. Neither EEC nor QREC were detected in MO. The pulsotypes of EEC and QREC isolates differed between NP and RA. Our study suggests that deer of the Nara Prefecture are potential carriers of ARB, but long-distance dissemination is unlikely due to limited deer movement.

Low potential of persistence and dissemination of antimicrobial-resistant Enterobacterales by wild nutria (Myocastor coypus) in a local river of Gifu Prefecture.

Environmental pollution caused by antimicrobial resistance is a global public health concern. To investigate the contribution of nutrias (Myocastor coypus) to the presence of extended-spectrum ß-lactamase (ESBL)-producing Enterobacterales in the Ijira River, prevalence of ESBL-producing Enterobacterales in their feces was examined using deoxycholate-hydrogen sulfide-lactose agar containing cefotaxime. Additionally, the composition of the fecal microbiota of nutria was examined using DNA metabarcoding analysis of the 16S ribosomal RNA gene and compared with that of Amami rabbit, deer, fox, and raccoon dog. The absence of ESBL-producing Enterobacterales and substantially lower abundance of Enterobacterales was observed in the feces of nutrias than in those of other wild mammals. Our results suggest the low potential of antimicrobial-resistant Enterobacterales persistence and dissemination by nutria.

A survey of antimicrobial-resistant Escherichia coli prevalence in wild mammals in Japan using antimicrobial-containing media.

The emergence and spread of antimicrobial-resistant bacteria and resistance genes pose serious human and animal health concerns. Therefore, to control antimicrobial-resistant bacteria in the environment, the status of antimicrobial resistance of Escherichia coli in a variety of wild mammals and their prevalence were examined using antimicrobial-containing media. In total, 750 isolates were obtained from 274/366 (74.9%) wild mammals, and antimicrobial-resistant E. coli was detected in 37/750 isolates (4.9%) from 7 animal species (26/366 [7.1%] individuals). Using antimicrobial-containing media, 14 cefotaxime (CTX)- and 35 nalidixic acid-resistant isolates were obtained from 5 (1.4%) and 17 (4.6%) individuals, respectively. CTX-resistant isolates carried blaCTX-M-27, blaCTX-M-55, blaCTX-M-1, and blaCMY-2, with multiple resistance genes. Fluoroquinolone-resistant isolates had multiple mutations in the quinolone-resistance determining regions of gyrA and parC or qnrB19. Most resistant isolates exhibited resistance to multiple antimicrobials. The prevalence of antimicrobial-resistant bacteria observed in wild mammals was low; however, it is essential to elucidate the causative factors related to the low prevalence and transmission route of antimicrobial-resistant bacteria/resistance genes released from human activities to wild animals and prevent an increase in their frequency.

Isolation of extended-spectrum ß-lactamase-producing Escherichia coli from Japanese red fox (Vulpes vulpes japonica).

Antimicrobial resistance is a global concern requiring a one-health approach. Given wild animals can harbor antimicrobial-resistant bacteria (ARB), we investigated their presence in 11 fecal samples from wild animals using deoxycholate hydrogen sulfide lactose agar with or without cefotaxime (CTX, 1 mg/L). Thus, we isolated CTX-resistant Escherichia coli from two Japanese red fox fecal samples. One strain was O83:H42-ST1485-fimH58 CTX-M-55-producing E. coli carrying the genes aph(3″)-Ib, aph(3')-Ia, aph(6)-Id, mdf(A), sitABCD, sul2, tet(A), and tet(B), whereas the other was O25:H4-ST131-fimH30 CTX-M-14-producing E. coli carrying mdf(A) and sitABCD and showing fluoroquinolone resistance. Thus, the presence of extended-spectrum ß-lactamase producers in wild foxes suggests a spillover of ARB from human activities to these wild animals.

Third-Generation Cephalosporin Resistance in Intrinsic Colistin-Resistant Enterobacterales Isolated from Retail Meat.

Consumption of retail meat contaminated with antimicrobial-resistant (AMR) bacteria is a common route for transmitting clinically relevant resistant bacteria to humans. Here, we investigated the genotypic and phenotypic resistance profiles of intrinsic colistin-resistant (ICR) Enterobacterales isolated from retail meats. ICR Enterobacterales were isolated from 103 samples of chicken, 103 samples of pork, and 104 samples of beef purchased from retail shops in Japan, using colistin-containing media, and their antimicrobial susceptibility was examined. Serratia spp. (440 isolates) showed resistance to cefotaxime (19 isolates, 4.3%), tetracycline (15 isolates, 3.4%), and other antimicrobials (<1%). Hafnia spp. (136) showed resistance to cefotaxime (12 isolates, 8.6%), ceftazidime (four isolates, 2.9%), and tetracycline (two isolates, 1.4%). Proteus spp. (39) showed resistance to chloramphenicol (four isolates, 10.3%), sulfamethoxazole-trimethoprim (four isolates, 10.3%), cefotaxime (two isolates, 5.1%), kanamycin (two isolates, 5.1%), and gentamicin (one isolate, 2.6%). Cedecea spp. (22) were resistant to tetracycline (two isolates, 9.1%) whereas Morganella spp. (11) were resistant to tetracycline (four isolates, 36.4%) and chloramphenicol (one isolate, 9.2%). The resistance genes blafonA, blaACC, and blaDHA were detected in cefotaxime-resistant Serratia spp., Hafnia spp., and Morganella spp. isolates, respectively. This emergence of antimicrobial resistance in ICR Enterobacterales may pose a public health risk.

Prevalence of Colistin-Resistant Bacteria among Retail Meats in Japan.

Colistin (CST) is considered the last resort for the treatment of infectious diseases due to multidrug-resistant bacteria. Since the mcr-1 gene has been reported in Enterobacteriaceae isolated from food, animals, and humans in China, the prevalence of CST-resistant bacteria has been of great concern. Here, we investigated the prevalence of CST resistance and plasmid-mediated colistin-resistance genes (mcr) in gram-negative bacteria isolated among retail meats in Japan. CST-resistant bacteria were isolated from 310 domestic retail meats (103 chicken meat, 103 pork, and 104 beef) purchased between May 2017 and July 2018 from retail shops in Japan using CST-containing media and antimicrobial susceptibility testing. The mcr gene was investigated in isolates with a CST minimum inhibitory concentration of ≥1 µg/mL. Excluding the intrinsically CST-resistant isolates, CST-resistant bacteria were isolated from 39 of the total chicken meats (37.9%), 19 of the pork samples (18.4%), and 18 of the beef samples (17.3%). A total of 459 isolates were identified, out of which 99 were CST-resistant. CST resistance (resistance breakpoints: Aeromonas, >4 µg/mL; others, >2 µg/mL) was found in Aeromonas spp. (48/206, 23.3%), Yersinia spp. (5/112, 4.5%), Escherichia coli (23/39, 59%), Citrobacter spp. (4/26, 15.4%), Klebsiella spp. (2/23, 8.7%), Raoultella spp. (2/16, 12.5%), Enterobacter spp. (7/14, 50%), Pseudomonas spp. (1/8, 12.5%), Pantoea spp. (5/7, 71.4%), Ewingella spp. (1/4, 25%), and Kluyvera spp. (1/2, 50%). The mcr gene was detected in 16 isolates: mcr-1 in 14 isolates of E. coli from 10 chicken samples (9.7%), and mcr-3 in two isolates of Aeromonas sobria from pork and chicken samples (each 1.0%). The findings of this study highlight the necessity of surveillance of CST resistance and resistance genes in bacteria that contaminate retail meats.

Prevalence of antimicrobial resistance in bacteria isolated from Great Cormorants (Phalacrocorax carbo hanedae) in Japan.

Wild birds are recognized as disseminators of antimicrobial-resistant (AMR) bacteria into the environment. Here, we isolated AMR indicator bacteria from 198 Great Cormorant cloacal swabs collected in Shiga (n=90), Oita (n=52), Gifu (n=29), and Gunma (n=27) Prefectures, Japan, in 2018 and 2019. In total, 198 Aeromonas spp. and 194 Escherichia spp. were isolated, and their antimicrobial susceptibility was examined. Aeromonas spp. were resistant to colistin (8.6%), nalidixic acid (4%), and other antimicrobials (<2%), with 3.0% positivity for mcr-3. Escherichia spp. showed resistance to colistin (3.1%), ampicillin (2.6%), tetracycline (2.1%), and other antimicrobials (<2%). This study shows the presence of AMR bacteria in Great Cormorants, indicating that these birds potentially disseminate AMR bacteria.

Association between the blaCTX-M-14-harboring Escherichia coli Isolated from Weasels and Domestic Animals Reared on a University Campus.

Antimicrobial-resistant (AMR) bacteria affect human and animal health worldwide. Here, CTX-M-14-producing Escherichia coli isolates were isolated from Siberian weasels (Mustela sibirica) that were captured on a veterinary campus. To clarify the source of bacteria in the weasels, we examined the domestic animals reared in seven facilities on the campus. Extended-spectrum ß-lactamase (ESBL)-producing E. coli were isolated on deoxycholate hydrogen sulfide lactose agar, containing cephalexin (50 µg/mL) or cefotaxime (2 µg/mL), and were characterized with antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE), replicon typing, and ß-lactamase typing analyses. Next-generation sequencing of the ESBL-encoding plasmids was also performed. CTX-M-14 producers isolated from both domestic animals and weasels were classified into six clusters with seven PFGE profiles. The PFGE and antimicrobial resistance profiles were characterized by the animal facility. All CTX-M-14 plasmids belonged to the IncI1 type with a similar size (98.9-99.3 kb), except for one plasmid that was 105.5 kb in length. The unweighted pair group method with arithmetic mean (UPGMA) revealed that the CTX-M-14 plasmid in the weasel isolates might have the same origin as the CTX-M-14 plasmid in the domestic animals. Our findings shed further light on the association of antimicrobial resistance between wild and domestic animals.

Antimicrobial susceptibility of Escherichia coli isolates obtained from wild mammals between 2013 and 2017 in Japan.

The emergence and prevalence of antimicrobial-resistant bacteria in wild animals are a great concern for public health. A total of 963 Escherichia coli isolates from 475 wild mammals (242 sika deers, 112 wild boars, 113 small mammals, 4 Japanese badger, 2 Tokara cows, and 2 Amani rabbits), collected between 2013 and 2017, were examined for antimicrobial susceptibility. Resistance to at least one antimicrobial was observed in 92 of 963 isolates (9.3%). No isolates exhibited resistance to carbapenem (meropenem). Resistance to third-generation cephalosporin (cefotaxime) and fluoroquinolone (ciprofloxacin) was observed in less than 1% of the isolates. Thus, low prevalence of bacterial antimicrobial resistance was observed in wild mammals between 2013 and 2017 in Japan.

Effects of Antimicrobial Administration on the Prevalence of Antimicrobial-Resistant Escherichia coli in Broiler Flocks.

The increase in antimicrobial-resistant (AMR) bacteria caused by antimicrobial usage is a public health problem. We investigated the proportion of cephalexin (LEX)-resistant bacteria in fresh feces obtained from antimicrobial-free broilers in three flocks at ＜15, 15-40, and＞ 40 days old. DHL agar plates containing 25 µg/mL LEX (DHL-L) showed LEX-resistant bacteria in all flocks at ＜15 days old and in one flock at ＞ 40 days old. The bacterial counts on DHL and DHL-L were 105-108 colony forming units (CFU)/g feces and ＜102-105 CFU/g feces, respectively. We also assessed the proportion of AMR bacteria in feces collected at 5, 12, 19, 26, 33, and 40 days old from two flocks treated with amoxicillin at 5-7 days old and co-trimoxazole at 24-26 days old. The proportion of ampicillin (AMP)-resistant bacteria was elevated at 12 and 26-33 days old on DHL containing 50 µg/mL AMP, while no increase in LEX-resistant bacteria was observed on DHL-L. All isolates tested exhibited AMP resistance at 12 days old, while most exhibited resistance to both AMP and trimethoprim/sulfamethoxazole at 26-33 days old. Our results suggest that antimicrobial administration influenced the selection of AMR bacteria with cross- and coresistance.

Association of Salmonella Serotypes with Quinolone Resistance in Broilers.

Fluoroquinolone is widely used for the treatment of bacterial diseases, and the emergence of quinolone resistance has become a serious concern in recent years, owing to an increase and inappropriate use of antimicrobials. Here, we attempted to understand the differences in the emergence frequency of quinolone-resistant bacterial variants in three Salmonella serotypes S. Infantis, S. Schwarzengrund, and S. Manhattan-which are mainly found in broiler industries in Japan. Emergence frequency tests for quinolone-resistant variants using enrofloxacin-containing agar plates and sequence analysis in the quinolone resistance-determining region (QRDR) of gyrA in DNA gyrase were performed. The results showed no significant difference in the emergence frequency among the three serotypes, and most of the resistant variants had mutations in the QRDR region. These findings suggest that differences in the serotypes tested are not associated with the emergence frequency of quinolone-resistant variants.

The occurrence of CTX-M-25-producing Enterobacteriaceae in day-old broiler chicks in Japan.

Day-old chicks from 3 hatcheries were placed on bedding paper and brought to a commercial broiler farm between January and July 2016. Sixty-six samples of the paper, which were stained with meconium droppings of the chicks, were collected and examined for isolation of cephalosporin-resistant Enterobacteriaceae. Cefotaxime (CTX)-resistant Klebsiella pneumoniae (1 isolate) and Enterobacter cloacae (4 isolates) were isolated from 5 (7.58%) of the 66 samples. Conjugation experiments revealed that the blaCTX-M-25 gene conferring CTX resistance was transferred from the K. pneumoniae isolate and 2 of the 4 E. cloacae isolates to Escherichia coli DH5α via IncA/C plasmids carrying the gene. Our results suggested that the blaCTX-M-25 gene originating from chicks may be spread among commercial broiler farms.

Gonadotropin-releasing hormone retards doxorubicin-induced apoptosis and serine/threonine phosphatase inhibition in ovarian cancer cells.

We recently demonstrated serine/threonine phosphatase (protein phosphatase 2A, PP2A), a crucial enzyme in apoptosis control, within the plasma membrane as well as soluble fraction. This study aimed to determine whether gonadotropin-releasing hormone (GnRH) affects the membrane PP2A-associated apoptosis and the enzyme activity in ovarian cancer cells. PP2A activity was assessed by measuring the dephosphorylation of phosphopeptide highly selective for the PP2A in plasma membranes isolated from ovarian cancer SK-Ov-3 and Caov-3 cells. Apoptosis was quantified by nuclear morphology after staining with Hoechst 33342 and by loss of plasma membrane phospholipid asymmetry using Cy3-conjugated annexin-V. Treatment with doxorubicin (1 microM) for 48 h caused parallel increases in the percentage of cells undergoing apoptosis (71.3+/-5.5% vs. 2.2+/-0.8% for control, P<0.01) and decrease in the membrane-associated PP2A activity (to 38.5+/-8.2% of control, P<0.01). In cells simultaneously incubated with GnRH agonist leuprolide (1 microM) for 48 h, the maximum doxorubicine-induced apoptosis and membrane PP2A inhibition were reduced to 38.4+/-6.2% (P<0.01) and to 82.1+/-7.3% of control (P<0.01), respectively. The GnRH agonist alone caused apoptotic cell death accounting for only 6.8+/-2.1% (P<0.01) and had no effect on membrane PP2A activity. These findings demonstrate that PP2A inhibition is closely coupled to the onset of apoptosis in ovarian cancer cells exposed to doxorubicin. GnRH agonist may protect against the inhibition of membrane-associated PP2A activity and thus retard doxorubicin-induced apoptosis, suggesting an additional activity of GnRH to protect ovarian cancer cells from stimulated apoptotic cell death.

Advanced indications for gonadotropin-releasing hormone (GnRH) analogues in gynecological oncology (review).

Gonadotropin-releasing hormone (GnRH) analogue has beneficial effects on the size and symptoms of endometriosis and uterine leiomyomas as a result of suppressing ovarian steroidogenesis. GnRH analogues are also the preferred treatment for advanced and even metastatic or recurred carcinomas originated from the reproductive tract. The original rationale for a GnRH analogue in the treatment was to block the endogenous gonadotropin and thereby steroid hormone secretion which was thought to stimulate tumor growth. However, more than 80% of ovarian and endometrial cancers express receptors for GnRH, and the analogues inhibit proliferation of the GnRH receptor-bearing tumor cells both in vivo and in vitro, supporting evidence for a direct antiproliferative effect. These receptors could be used for targeted chemotherapy (by tumoricidal agents linked to GnRH analogues) to improve antitumor effects and reduce side effects compared with conventional systemic chemotherapy. In addition to the anticancer action, GnRH analogues act to protect the gonads during radiation and/or chemotherapy by preferentially steering cells into cell cycle arrest with a decline in responsibility to the chemotherapy and radiation. In women who wish to maintain potential fertility, GnRH analogue therapy is successful in preventing the most critical postoperative complication, adhesion formation. The additional unrecognized benefits may add to the advantage of GnRH analogues in cancer management in gynecology.

Independent action of serine/threonine protein phosphatase in ovarian cancer plasma membrane and cytosol during gonadotropin-releasing hormone stimulation.

Reversible serine/threonine protein phosphorylation catalyzed by kinases and phosphatases 2A (PP2A) plays a crucial role in cellular growth and differentiation. We attempted to determine the subcellular location of PP2A in ovarian cancer cells and its regulation by gonadotropin-releasing hormone (GnRH), which is known to have anti-proliferative actions on ovarian cancers. Surgically removed ovarian cancers were screened for GnRH receptor expression prior to subcellular fractionations. PP2A activity was assessed by measuring the dephosphorylation of phosphopeptide highly selective for the PP2A in cytosol and membranes fractionated on a continuous sucrose density gradient. To assess GnRH effects, cloned cell lines were pretreated with or without a GnRH agonist. There were three peaks of PP2A activity, corresponding by marker enzyme analysis to the cytoplasm, plasma membrane and endoplasmic reticulum fractions. The kinetic analysis showed a different activity in cytosol and membrane; Km values for substrate of 185 microM and Vmax of 555 pmol/mg protein/30 min for cytosol, and 28 microM and 83 pmol/mg protein/30 min for plasma membrane, respectively. PP2A-specific inhibitor okadaic acid inhibited the cytosolic and membrane-associated activity by 50% when added at 2 nM and 50 nM (p<0.001). A 50% inhibitory effect of NaF was obtained at 0.5-1 mM for cytosol and 5 mM for membranes (p<0.001). In Caov-3 cells exposed GnRH, PP2A activity of plasma membrane increased by 1.3-fold (p<0.001) but that of cytosol was not affected. PP2A activity in the plasma membrane of ovarian cancer cells might be distinct from that present in the cytosol. The plasma membrane PP2A may be responsible for a portion of an increased ser/thr protein phosphorylation-dephosphorylation turnover that occurs during cell exposure to GnRH.